import edu.princeton.cs.algs4.Queue;
public class test {
    public static void main(String[] args) {
        Queue<Integer> test1=new Queue<Integer>();
        test1.enqueue(1);
        test1.enqueue(2);
        test1.enqueue(3);
        System.out.println(test1.peek());
        System.out.println(test1.peek());
        System.out.println(test1.peek());
    }
    

    
}
